Wood burning stoves have recently typically been provided with catalytic converters to remove creosotes to prevent them from coating insides of chimneys (fire hazards) and polluting the atmosphere. Bypass valves are typically used to bypass the catalytic converter during startup and refueling in order to prevent smoke spillage back into the house, caused by the flow resistance resulting from small openings and large surface area of the catalytic converter. Because of the flow resistance provided by the converter, if there is a leak in the bypass valve, there will be substantial flow of exhaust gases through it instead of the converter during operation.